Dynamometer-wattmeter.



DOLIVO-DOBROWOLSKY. v DYNAMOMETER WATTMETER.

APPLICATION IILED AUG.18, 1910 Patented May 6, 1913.

Inventor:

michael no'livo-nohr'owolsky Hisflctorne g.

wltnessesz .IICHAEL DOLIVO-DOBROWOLSKY, 0F WILMERSIDORF, GERMANY,AS$IGNOE TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

DYNAMOMETER-WATTMETER.

Application filed August 18, 1910. Serial No. 577,862.

Specification of Letters Patent.

Patented May c, 19113.

To all 20/20 122. it may concern lie it known that I, Micnnnr.Domvo-Donnowocsn'r, a citizen of the Swissltepubhc,

residing at \Vihnersdort, Germany.v have 111;

vented certain new and useful Improvements in Dynanu:mctcr vattmete rs',of which the following is a specification.

My invention relates to dynamometer wattmct crs and has for its objectan im provcmcnt in the construction of instruments of this character.

More specifically, the object of my invention is the construction of anelectro dynamometer wattliicter which shall be compact and simple,havcthe greatest possible torque, with the use. of as few ,ampere turns aspossible, and shallbe adapted for circuits of varying capacities.

For a further miderstanding of my l1lvention. reference may be had tothe accompanying drawing, wherc Figure I shows a vertical view,partially in section, of ameter constructed in accord- -ance with myinvention; Fig. 2 shows a top 25 yiewof a portion of the same, certaindetails being omitted; Fig". 3 shows the connections which I employ; and4 shows a vertical view of a portion ot' the meter.

Referring first to Fig. 1, the meter may be fastened to a suitablebase 1. 2 and 3 are magnetic cores, thc outer of which is formed as ahollow cylinder and the inner as a solid cylinder, these cores beingconcentric and spaced apart so as to have an air gap t between them.These cores I prefer to construct 0t a laminated silicon alloy, iron orsteel. l prcl'cr to use a silicon alloy of iron or steel r any othersuitable material having a high electric resistance so as to decreasethe iron losses in the core, for, as is well known. the iron losses in amagnetic core produce a phase displacement between lhc tlux in thecore-and the current flowing in the coil energizing the same and, itsuch losses are large, this phase displacement will be comparativelylarge. By dccruising the proportion of these losses, the phasedisplacement may also be decreased and thus the :urcuracy of theinstrument increased. They may be fastened together in any suitablemanner. Passing between the cores and so through the air gap andrevolving in the same is the voltage COll 5. which may be attached toshafts 6, 6 held in suitwith a suitable pointer and scale in the usualmanner, and as these devices form no. portion of my invention, I havenot illus? trated them. movable voltage coil is the stationary cm;-

In inductive. relation with the;

rent-coil T which I prefer to construct so that it shall be shorteircuited and consist ofa single turn composed of vertical bars joinedat their ends by conductors 8 and 9. Con-- ductor -9 may be inserted 'inthe base and shown in the drawing. The stationary current coil may beinsulated from the cores by insulation 10 and the cross piece 8 may havesurrounding it insulation 10'. Surroundin cross piece 8, or a portion ofthe current coi, is the magnetic core 11, having wound about. it athirdcoil 12 which is in inductive relai-i tion to it and the stationary coiland hence forms the primary of a transformer, of which the stationarycurrent coil forms the secondary winding. This may be better seen byreferring to Fig. 4,,which shows a view at right angles to that shown inFig.1 of member 8 and coil 12 with insulation 10'.

Beferringnow to Fig. 3, which shows the connections I employ, 14 and 15are conduc? -16, whose energy consumption it is desired to measure. The,voltage' coil 5 may be con,- nected directly across the. mains asshown, or in series with a resistance in the well known manner which Ihave not illustrated, and the third coil or the primary of thecurrenttransformer, of which-the stationary current coil forms thesecondary is connected in series withone of the conductors of thecircuit, as shown.

In case it'b' desired to measure circuits of varying capacities, crosspiece 8 may be; removed and the core and coils surrounding this crosspiece replaced by a suitablecore and coil having a difi'erent number ofturnii so that the ratio of transformation between the secondary and theprimary of thistransformer device may bechanged and the current flowingin the stationary short-circuited secondary coil -for'circuits of widelyvarying capacity will be of a substantially uniform magnitude. Suchsubstitution will be well understood by those skilled in the ablebearings. "lhis coil may be provided art.

While I have described a pret'crrml e1nbodiment of my invention, i donot limit myself to this embodiment but cool: in the appended claims tocover all embodiments which will be obvious to those -1lillc-l in theart and will not depart lroin the spirit of my invention.

Nhat .1 claim an new and desire to secure by Letters; Patent of t :e llllltll Slates. is:--

1. An elecli-o (lynamonieter \vallmetcr comprising in combination amovable voltage coil, a stationary short circuitcd cur rent coil ininductive relation therwvith. a magnetic core surrounding a portion ot'the current coil, a third coil, in inductive relation with the core andthe current coih and means permitting the removal of the core and thethird coil from the current coil.

2. An electro dyna'uiometer comprising in combination two concentriccores of magnetic material spaced apart, a movable coil passing betweenthe cores, a stationary short circuileil coil in inductive relation tothe movable coil and the cores, and a third coil in inductive relationto the short circuitecl coil.

3; An electro dynamometer Wattmeter comprising in combination twoconcentric cores of magnetic material spaced voltage coil movablebetween the cores, a stationary current coil comprising a single shortcircuited turn in inductive relation to the cores and the voltage coil,a magnetic. core mil-rounding a portion of the current coil in inductiverelation thereto, and a third coil in inductive relation with said coreand the current coil.

4-. An, electro dynainon'ieter wattmeter comprising in combination twoconcentric cores composed of magnetic material of" high electricresistance spaced apart, a voltage coil movable between the cores, astationary current coil comprising a single PhOIt cira'parl', a

cuited turn in inductive relation to the cores i and the voltage coil, acore surrounding a portion of the current coil, :1 third coilsurrounding said core in inductive relation to it and the current coiland means permitting the removal of said core and coil from the currentcoil.

In witness whereof, I have hereunto set my hand this 6th August, 1910.

MICHAEL DOLIVO-DOBROWOLSKY.

Witnesses:

LEMP RIoHAnn, JULIUS RUMLAND.

